1. Field of Invention
The invention relates to a milling apparatus for comminuting soil, rock or other material.
2. Description of the Related Art
For excavating soil, suitable digging devices such as excavators are known. However, these are not readily capable of breaking through solid top layers, such as concrete or asphalt, or picking up rock at depth, or mixing the excavated material. Combined digging, mixing and milling equipment has therefore been developed. One such system is known for instance from German Patent Disclosure DE 199 07 430 A1. This system has an excavator bucket that is provided with a miller on its back side. The miller is accommodated in a milling chamber and protrudes from it. Between the milling chamber and the receiving chamber of the excavator bucket, there is an opening, embodied for instance in the form of a sieve. Thus granular material that occurs in the milling process can be collected in the excavator bucket, making rational and versatile work possible. The excavator bucket can be used both like a conventional excavator bucket and additionally as a rock miller.
From German Patent Disclosure DE 42 13 523 A1, a mobile milling loading system is known that is formed by a rock miller in the vicinity of which a pivotable bucket is located. The pivotable bucket serves to receive the material detached by and spun away from the rock miller.
So-called bucket separators are also known, which are capable of receiving a loose mixture of material and separating it into a coarse fraction and a fine fraction. A bucket separator of this kind has a bucket whose bottom is formed by a grate provided with a plurality of rollers. The rollers carry disk elements and rotate in the same or opposite directions. They separate out the fine material, which can fall through between the rollers, while coarse material remains in the bucket.
In practical operation, all the individual tasks named occur to a greater or lesser extent. Sometimes, ditches or trenches have to be excavated, and existing rock can be expected. If the extracted material is to be reincorporated, then often coarse fractions have to be separated out. If other materials, such as material from a demolished building, construction trash or the like that is to be incorporated on site is present, then these materials must sometimes be comminuted and classified. For each of these individual operations, special tools are required.